Thrust-pin for winding-drums.



S. J. BALDWIN & J. W. SLY.

THRUST PIN FOB WINDING DRUMS- APPLICATION IILBD JUNE 13, 1914.

9AM. Patented Feb. 23, 1915.

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IINITED @TATEd PATENT UFFIMET.

SAMUEL J. BALDWIN, OF TACOMA, AND JOSEPH W. SLY, OFEATONVILLE,WASHINGTON.

THRUST-PIN FOR WINDING-DRUMS.

Specification of Letters Patent.

Patented Feb. 23, 1915.

To all whom it may concern:

Be it known that we, SAMUEL J. BALDWIN and JOSEPH W. SLY, citizens ofthe United States, residing at Tacoma and Eatonville, respectively, inthe county of Pierce and State of Washington, have invented certain newand useful Improvements in Thrust- Pins for Winding-Drums, of which thefollowing is a specification.

This invention relates to improvements in devices for applying endwisemovements to a frictional clutch element, such as employed in hoistingand hauling engines, to engage a normally loose drum with a power drivenclutch element to render the drum operative.

The object of our invention is the provision of inexpensivelyconstructed and efficient means whereby the friction which insuesbetween the take-up screw and the thrust-pin of such a device is reducedto a minimum with an absence of heat thereat and with an increase in thedurability of such thrust-devices and with an improvement in theoperation of the engine.

With these ends in view, the invention consists in the novelconstruction and adaptation of devices, as will be hereinafter describedand claimed.

In the accompanying drawings, Figure 1 is a longitudinal sectional Viewof a portion of a hauling engine with our invention applied thereto.Fig. 2 is a detail sectional view, to an enlarged scale, showing partsof the thrust-pin elements and an interposed ball which is shown inelevation.

The reference numeral 5 designates a drum loosely mounted on a shaft 6having rigidly mounted thereon a cup frictional element 7. The latter isprovided with peripheral spur-teeth 8 whereby the element is rotated bymeans of a pinion, not shown, to drive the shaft. Said drum is providedat one end with a cone 9 adapted to be engaged with the cup element 7when the drum is moved axially in opposition to a spring 10 tending toyieldingly hold the drum in disengaged position with respect to thepower driven clutch element 7.

The shaft 6 is journaled in bearing boxes 11 and 11 of the machineframe, and secured to the latter is a block 12 which is provided with ascrew-threaded hole 13 and constitutes a fixed nut for a take-up screw14: which may be operated by a handle arm 15. The screw 14 extends intoan axial bore 16 of the shaft and communicates with a slot 17 extendingdiametrically through the shaft. Provided in said slot is a key 18having protruding ends which are juxtaposed with the drum.

The aforedescribed parts are substantially slmilar to what are nowcommonly used in the class of machines to which the invention pertains;but in addition thereto is usually employed a thrust-pin having its endsrespectively engage the take-up screw 14: and the key 18 so that whenthe screw is properly turned, it will exercise, through the medium ofthe referred to pin, motion to the key which, in turn, imparts axialmovement to the drum for coupling the latter with the driving element 7.

Inasmuch as the force necessary to be applied to a thrust-pin of thischaracter to maintain the drum in engagement is considerable, andbecause the screw 14: does not rotate with the shaft, the frictionhitherto obtaining between the thrust-pin and the key, or the screw, hasbeen sufficient to cause the pin to become excessively hot so as todestroy the pin and oftentimes cause it tobecome welded to one or theother of the parts in contact therewith.

According to the present invention, we provide a pin comprised of aplurality of spaced members A and B arranged in axial alinement in theshaft-bore l6 and interpose anti-friction balls C between said membersand between the screw 14: and the adjacent member A.

The ends of the screw and of the members against which the balls bear,are each formed with a concavity D of greater radius than that of aball, and centrally of each such depression the screw, or member, isground, as at E, Fig. 2, to afiiord a socket of substantially the samecurvature as the periphery of a ball. By such devices there is affordeda seat at the center of a member for a ball and surrounding the latteris an annular recess F for the admission of lubricating material towithin a short distance of the axis of the pin members.

In practice, the balls are made of slightly less diameters than theshaft-bore so that when the screw is retracted the balls drop out ofalinement with the pin-members, and when the screw is again utilized,the concave faces D at the ends of the pin-members will direct the ballsinto the sockets or seats E therefor.

The lubricant oil or grease may be supplied to the shaft bore from achamber 19 at the end of the shaft and when the balls drop into thelubricant some of the latter Will adhere to the balls to be subsequentlycarried by the latter into the sockets.

What We claim as our invention, is

1. In apparatus of the class described, the combination With the shafthaving an axial bore in one end thereof and a slot extendingdiametrically through the shaft and co1nmunicating with said bore, aclutch element secured to the shaft, a drum loosely mounted on the shaftand provided with a clutch element engageable with the aforesaidelement, a key extending through said slot and engaging the drum, a nutfixedly secured to the machine-frame, and a screw engaging said nut andextending into the shaft bore, of thrust-pin devices located intheshaftbore between said screw and the key and comprising a pluralityof members having sockets in their adjacent ends, and a ball interposedbetween said members and adapted to seat in said sockets.

2. In apparatus of the class described, a plurality of pin membersalternating with balls, said pin members being formed in their ends withconcavities of greater radii than the balls and sockets formed in thecenters of the respective concavities of radii corresponding with theballs.

3. In apparatus of the class described, a take-up screw and a pinmember, concavities formed in the opposing ends of the screw and pinmember, and a ball of less diameter than said pin member interposedbetween the screw and said member and arranged to seat in both of saidconcavities when the screw is rendered operative.

SAMUEL J. BALDWIN. JOSEPH W. SLY.

\Vitnesses for Samuel J. Baldwin:

J. M. G

NORMAN J. BRUEN, J. B. CARLTON.

(Ionics of this patent may be obtained for five cents each, byaddressing the Commissioner of IPatents, Washington, D. G.

